With its usage in sweeteners and bioethanol seeing it compete increasingly with, in particular, corn, sugar is looking more and more like an agricultural commodity which should come with a kernel that should spill out of combine harvesters.

That has implications for sugar prices, which look increasingly likely to move in step with grain markets, rather than being so much controlled by weather in top producer Brazil, or export policy in second-ranked India.

"Sugar has traditionally been seen as a soft commodity but today we see much greater similarities with the corn market," Toby Cohen, director at Czarnikow, said.

"Corn and sugar are becoming increasingly linked in the global markets, something that has implications for the prices of both commodities."

Substitution dynamics

The trade-off is evident in markets such as that for ethanol in Brazil, the top sugar producer, which thanks to market signals has turned more of its cane output to sweeteners, rather than biofuels.

This has left the country, historically the top ethanol exporter, on track to become a net importer "as US corn ethanol has been imported to help alleviate supply problems".

Conversely, buoyant Brazilian ethanol exports in 2006-07 and 2008-09, when tight US corn supplies were sent prices of the grain soaring, were "critical in clearing surplus sucrose from the sugar market", clearing the way for higher sugar prices and a stimulus to output.

The degree of substitution in sweeteners markets is more limited, by regulations and differing specifications between sugar and corn products, and amounts to 3m-5m tonnes a year.

'Arbitrage opportunities'

Nonetheless, in both sweeteners and energy, substitution is to become "more efficient and potentially constrained by policy", with the US, for instance, expected to reduce trade barriers.

"Though the relationship between corn and sugar is indirect, as it driven by the substitution of corn and sugar cane or beet as feedstocks, we expect to see greater interaction between prices," Czarnikow said.

"The opportunity for arbitrage between corn and sugar will increase.

"With the demand for corn and sugar growing, coupled with rising demand for energy, there is no question that arbitrage opportunities between physical commodities are on the increase."

Bigger earner

As for who will be the winner of the corn-sugar dynamic on the production side, Czarnikow stopped short of backing either the corn or sugar industries.

But, on a revenue side at last, the sugar merchant sees sugar as the bigger earner.

The US corn industry receives the equivalent of some $4,400 per hectare of corn industry, assuming the grain is converted into high fructose corn syrup, equivalent to 6.1 tonnes of sugar per hectare, plus extras such as feed, meal and oil

Brazil's cane industry achieved sugar output of 10.5 tonnes of sugar per hectare, with French beet growers producing the equivalent of 12-14 tonnes of sugar per hectare.

"Despite corn processing providing further income from byproducts… sugar crops still generate a greater revenue per hectare for sweeteners or ethanol, from both sugar beet and sugar cane," the London-based group said.